fn main() {
    // 加法
    let sum = 5 + 10;
    println!("和 = {}", sum);
    // 减法
    let difference = 95.5 - 4.3;
    println!("差 = {}", difference);
    // 乘法
    let product = 4 * 30;
    println!("乘积 = {}", product);
    // 除法
    let quotient = 56.7 / 32.2;
    let truncated = -5 / 3; // 结果为-1
    println!("quotient = {}, truncated = {}", quotient, truncated);
    // 取余
    let remainder = 43 % 5;
    println!("余数 = {}", remainder);
}
